Development of a complete transient microchannel heat sink model

microchannel heat sinks are considered a strong candidate for meeting the increasing cooling needs of high-power microprocessors of today and the significant future. Such heat sinks are capable of dissipating impressive amounts of energy, as a result of high attainable heat transfer and favorable heat transfer surface area to volume ratios. The majority of microchannel heat sink studies performed to date have dealt with the steady state analysis of constant power density devices. On the contrary, power densities of microprocessors vary with both location and time. This variation of power leads to reliability-threatening thermomechanical stresses in the device. Thus, dimensional and transient power fluctuations are important considerations in the study of potential cooling solutions. The thermal response of a microchannel heat sink cooling a device with power generation varying both dimensionally and with time is studied herein. A full 3-dimensional numerical model is developed and validated in order to analyze the thermal behavior of an entire microprocessor and the microchannel heat sink employed. The effects of implementation of two-way fluid flow, wherein neighboring channels in the sink have opposite fluid flow directions is also investigated.